This is the timeline of the Universe from Big Bang to Heat Death scenario. The different eras of the universe are shown. The heat death will occur in around 1.7×10¹⁰⁶ years, if protons decay.^{[citation needed]}

This article relies largely or entirely on a single source. (August 2021)

It has been suggested that Graphical timeline of the universe be merged into this article. (Discuss) Proposed since February 2024.

Usually the logarithmic scale is used for such timelines but it compresses the most interesting Stelliferous Era too much as this example shows. Therefore, a double-logarithmic scale s (s*100 in the graphics) is used instead. The minimum of it is only 1, not 0 as needed, and the negative outputs for inputs smaller than 10 are useless. Therefore, the time from 0.1 to 10 years is collapsed to a single point 0, but that does not matter in this case because nothing special happens in the history of the universe during that time.

${\displaystyle s={\begin{cases}\log _{10}\log _{10}year&{\mbox{if }}year>10{\mbox{ , corresponding to }}year=10^{10^{s}}\\0&{\mbox{if }}0.1\leq year\leq 10\\-\log _{10}(-\log _{10}year)&{\mbox{if }}year<0.1{\mbox{ , corresponding to }}year=10^{-10^{-s}}\end{cases}}}$

The seconds in the timescale have been converted to years by ${\displaystyle second/31557600}$ using the Julian year.

• Fred C. Adams; Greg Laughlin (19 June 2000). The Five Ages of the Universe: Inside the Physics of Eternity. Simon and Schuster. ISBN 978-0-684-86576-8.